Monkey Head Nebula (NGC 2174/2175)

NGC 2175 is today recognised as a part of SH2-252, an extended H-II region in direction of the galactic anticenter. If we accept NGC 2175's distance to be 7200 light-years, it extends some 84x64 ly in true physical extent, which makes it about twice as big as the Great Orion Nebula.